text:
Can a simulator (FFS) be used in place of a Technically Advanced Aircraft (TAA) to meet the commercial experience requirements?
14 CFR 61.129(a)(3)(ii) lists the aeronautical experience requirements for a commercial certificate. It says:

(ii) 10 hours of training in a complex airplane, a turbine-powered
  airplane, or a technically advanced airplane (TAA) that meets the
  requirements of paragraph (j) of this section, or any combination
  thereof. The airplane must be appropriate to land or sea for the
  rating sought;

With the changes to this regulation to allow TAAs, does the FAA allow simulator (FFS) hours in place of the TAA hours?

This question seems better posed to the FAA, than to random strangers on the Internet who may or may not know what they are talking about...

I'm not sure what you're asking, can you expand your question? Are you asking if FFS time can be used in lieu of TAA time for the requirements in (a)(3)(ii)? If you can quote the specific part of the regulation that you're asking about, that would be very helpful.

Yes, that is exactly what I'm asking @Pondlife. Basically the answer if an "airplane" can be considered also Full Flight Simulator (Class D for example) the way I can log landings and approaches to satisfy currency requirements.

I'm still confused: 61.129 is about the requirements for a commercial pilot certificate; currency requirements are in 61.57. Are you asking about using a simulator to maintain instrument currency?

I was just mentioning the subject of currency because it can shows that a FFS can be used in lieu of an actual airplane. I was asking if the same can be used for TAA for commercial pilot requirements.

Thanks for clarifying your question! I've edited it to match what you just said in the comments; if I got it wrong then of course please roll back or edit further as needed.

You can't use a simulator for this time because the regulation specifically requires training time in an airplane; there's no mention of using a simulator. If you look at some of the wording in the currency regulations in 61.57 (for example) you can see that when the FAA allows you to use  a simulator they state it explicitly:

The takeoffs and landings required by paragraph (a)(1) of this section
  may be accomplished in a full flight simulator or flight training
  device that is [...]
A pilot may accomplish the requirements in paragraph (c)(1) of this
  section in a full flight simulator, flight training device, or
  aviation training device provided [...]

It would require a lot of digging to come up with proper citations, but a flight school can contract with a certificated part 142 training center as part of its curriculum. The part 142 school can provide type specific training on a sim. What I'm gathering is that what the op asks can be done through part 142 as long as both training centers have FAA-approved curricula. I can't find anything, though, about training outside an FAA-approved flight school.

@TomMcW I think we have a question or two about sim hours in a part 141 course, but I can't remember any part 142 questions here offhand. It might make a good self-answered question if you can dig up the details :-)

The problem is, part 141 and 142 stuff is all done by the FAA on a case-by-case basis. The curriculum has  to be submitted and approved, so each training center would have its own set of rules as to what it can and can't do. FWIW, I'd say that's what part 142 is all about. Certifying sim training centers so that all training facilities don't need to have all types of aircraft. I'd be willing to bet if you contacted a 142 center they would have a way to do what the op is asking, but it may require that they get the rest of their CPL training through a part 141 school.

We operate a Part 142 school with three sims (2 x Level C and one Level D) and we get asked all the time about this. Bottom line is that the sim use has to be spelled out in the regs or be part of an approved Part 142 training program.


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Where can I find a navigation database for Brisbane?
Does anyone know of a database that details the GPS locations of beacons within Brisbane; or a data-set that tells me air routes and associated en-route beacons, way points etc.?
I'd like to be able to plot a course on a map (Google, Bing, etc) from A to B given an air route or flight plan. SkyVector looks very similar to what I'm trying to achieve.

have you checked out apps like foreflight or Flight Plan they may have what you are looking for

SkyVector already gives you GPS coordinates for every waypoint on your route in the PDF (click on "Nav Log"). Do you need anything additional?

"SkyVector looks very similar to what I'm trying to achieve." To make it easier to answer your question, please explain what you need that Skyvector does not already offer

I'm capturing ads-b messages once I receive an identification message I call the flightaware ap to retrieve the flight data. Within this satanic is the filed flight plan. Is need a database that holds the GPS coordinates of the relevant navigation beacons and presumably the way points of the airway the aircraft is one.

I'm trying to plot these points on my a map so I can track the aircraft. Ultimately the aircraft position to the filed flight plan will feed a machine learning model to accommodate ATC changes to the plan. Hope that makes sense.

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Drop the rope or drag the rope?
I was the safety officer at a glider operation earlier this year and we had a new tow pilot who forgot to drop the rope. By radio, I instructed him to drop the rope before landing. The downsides of this is that it would temporarily leave the rope in the middle of the grass field where an aircraft might run over it, and also someone would have to golf cart out to retrieve the rope.
Later, when he found out about it, the chief tow pilot got angry about this and said the tow plane should have landed with the rope attached and dragged it back to the launch location. I thought this was unwise because this could damage the rope, or if the rope were to catch on something as the plane landed, it could have dangerous consequences for the tow pilot. Also, I have seen loose tow ropes whip around. Considering that there is a metal buckle at the end of the rope, imagine that thing whipping around. If the plane landed with the rope attached, I was picturing that buckle whipping into a bystander or a parked plane.
Of course, the third possibility is that he could do a go around, fly all the back and do the rope drop correctly. The disadvantage of this is that it would delay the return of the tow plane for another 10 minutes while he did the go around, and we had multiple people waiting for tows.
What is the best procedure?

As a non-glider pilot, my instinct is to notice that all of the drawbacks from the first ones are safety related whereas the last one is logistical. Based on that, it seems to me that the circuit and controlled drop would absolutely be the most wise procedure.

As a glider pilot, I have already seen the end of a dropped rope (the metal ring normally attached to the tow plane) that had penetrated roughly 30 cm in soft soil, and imagined the consequences of replacing this soil with someone's head. So there are also some risk associated with that drop. Of course, it is not dangerous if the drop occurs far from anyone, but I can imagine the temptation of dropping it "closer" to the ground crew.

Place I flew gliders out of always dragged the rope. I never saw it dropped.

There is a safety piece on the rope designed to break in case of excessive force. It helps prevent damage to the glider and tow plane during a tow, but it would also break in case the rope should catch on something during a landing while dragging the rope, so that should not be an issue.

@J.Hougaard That is not true. In most cases the entire rope has a failure rating. Sometimes, when a lightweight glider is flown, there is attached a "weak link" to reduce the rope's rating, however, even in that case it would be preferable to use a lower-rated rope rather than a weak link. In any case, the rope involved was a normally rated rope with no weak link. The rope holds with sufficient force that if it caught on something solid while the tow plane was landing, it could cause a serious problem.

Agreed with @zeta-band -- I flew gliders for 8 years at a field on the northern edge of KPHL's mode C veil and never saw a towplane (purposely) drop a rope for a non-emergency.  We operated out of a grass field surrounded by trees on most sides (maybe 10 miles south of KCKZ) and never had problems with towplanes landing with the rope attached.  When I first arrived, SOP was to put a wiffle ball on the tow rope so that "flew" behind the towplane a little better and had some more protection on the ground, but that was dropped without much issue a few years later.

@TylerDurden It certainly is true where I used to fly, but obviously it can differ from place to place

@TylerDurden, I see that you rolled back my title edit, which is fine. Could you please change the title such that it is a clear question? See this meta discussion. Thank you.

In Dunstable airfield (London Gliding Club) tugs have tow rope attached all the time, and it does not cause any troubles.

"I was the safety officer at a glider operation earlier this year and we had a new tow pilot who forgot to drop the rope. By radio, I instructed him to drop the rope before landing."-- this confuses me.  Where was the plane supposed to drop the rope?  Where was the plane located when the radio instruction was given?  What is the difference between the place where the rope was actually dropped, after receiving the radio instruction, and the place where the rope was supposed to be dropped?

I'm familiar with a glider club operating operating off a very long, wide, paved runway.  No one ever drops the tow rope from the air at this club.

To start: I flew gliders for 8 years at a field on the northern edge of KPHL's mode C veil and never saw a towplane (purposely) drop a rope for a non-emergency.  We operated out of a grass field surrounded by trees on most sides (maybe 10 miles south of KCKZ) and never had problems with towplanes landing with the rope attached.
There are some factors here that feed into this.  That particular field (http://www.pgcsoaring.com/) has generally well taken care of and is a completely turf field.  I think we added some lime markings to denote a landing box on our usual landing runway, but that's about it.  I have a picture of the runways used for normal operations below.  Takeoffs were started on the far right on runway 25 (picture has been rotated), and landings, typically, were facilitated on the runway marked by a dashed line.

Now, something that isn't quite clear from the overhead views are the trees.  At the far right hand side of 07-25, you have a stand of trees (and two hangers) that go up 40-50 feet.  Landing over these, particularly with a tow line, can put you out in the boonies if you want to make sure that the tow line isn't dragging through the trees.  The FAA Glider Flying Handbook (https://www.faa.gov/regulations_policies/handbooks_manuals/aircraft/glider_handbook/media/gfh_ch12.pdf) indicates that a 200 ft tow rope can "fly" about 130 ft below a towplane, so clearance in that dimension is critical.  The pictured field actually has 3 operating runways (07-25, 01-19, and 13-31) and, on the approach to each (save 25), there are no trees near the runway threshold or the runway is situated at the top of a significant hill.
Insofar as ground abrasion goes, I'd see wear and tear on a towline over time, but it was relatively slow accumulation.  Slow enough that you could track it by rope checks at the weak link (if in use) and tow hook prior to each flight...which you are probably doing anyhow.  We always had a spare rope spliced and on a reel so that an in-use line could be quickly replaced during normal operations (maybe a minute or less during a regular takeoff if it was coordinated well).  But that's more or less semantics: the point is, for the turf field we had, which was well-cleared of rocks, branches, or man-made debris, there were no problems with dragging a rope over the ground provided that pilots and line crew were doing the routine safety checks that they would be doing regardless.  Not dropping a tow line also kept down non-airplane vehicle traffic on the field during operations (i.e., it eliminated the need for another runner to get the tow line, especially when aircraft are anticipated to be landing).
The Glider Flying Handbook has this much more to say about landing with a tow rope (GFH 12-10):

Landing with the tow line attached is not prohibited by
regulation; however, the following points should be considered:

Obstructions are cleared by more than the tow line
length (altimeter lag considered).

The field is well turfed. It is simply inviting early
tow line failure from abrasion to land with the tow
line on hard ground or paved runways. Landing with
the tow line should never be attempted unless the
field has clear approaches and is at least 2,500 feet
in length.

Other situations require the tow line to be dropped, normally
in the glider launch area, during short approach to the
runway. If the tow line is to be dropped, the tow pilot must
be constantly aware of the launch area situation. The tow
line drop area must be defined and ground personnel must be
briefed and aware of the drop area. Ground personnel must
stay clear of the drop area, and the presence of an individual
in the drop area requires an immediate go-around by the pilot
of the tow plane without dropping the tow line.

Perennial debate.  When I towed, at my annual checkout, I was required to drop the rope.  There were several times that I did drop the rope, but 98% of the time, I landed with the rope.  All the ops people knew where it was, I knew where it was, and the other tow pilots knew where it was.
Besides, normally we were charged with getting to the ground quickly to get another tow up. So full authority slips, etc. all resulting in a steep approach with no danger of hitting the trees at the perimeter of the airport.
From my perspective there are risks either way, and I prefer not dropping anything prior to landing.  For one thing, it takes time, and when 3 or four planes are towing, and there are gliders recovering, and now tow planes have to come in for a low pass to drop the rope, it gets even more chaotic.  Chaos precedes stupid things happening.
The tennis ball trick is nice, but I just used a short streamer of surveyor tape.  It kept people busy trying to figure out the color code (pink, orange, green, chartreuse, fuscia, you name it.  I heard all kinds of theories, but each morning, I would just pick a 2 ft section of one tape or another from my trunk.  Or let some young kid decide.
That streamer got more attention to where the rope was, though.

I highly second the comment of "chaos precedes stupid things happening." I cannot agree with that enough.

You can drop the rope while on short final right at the start of the runway. You'll be landing upwind anyway and turning back around for the glider to get hooked up. It does require a wide enough field for the drop zone to be away from the prep zone.

@ratchetfreak near the start of the runway are the people preparing for flights, and gliders being queued, often on both sides of the runway. That would not be a safe place for the drop.  When I drop, I do a low pass, and drop the rope in the center of the runway, then go around and land after a circuit (4 min). For example, I might land long, while another tow is hooking up at or near the threshold of the runway.

@mongo that's why I mentioned the wideness of the field so an area can be reserved for the drop.

@ratchetfreak perhaps at your operation, but not at the one I towed at. It would absolutely be unsafe to drop at the threshold of the runway with operations going on.

To add another datapoint, I flew gliders in Argentina for 15 years, in many airfields (both club operations and competitions with up to 80 gliders) and I very rarely saw a rope dropped by a tow plane. Our club often did 30 to 40 tows per day on weekends, so it would have made a big difference to have to retrieve the rope each time. Wear and tear from dragging during the landings was not a big issue; we had to replace ropes from time to time, but it was a very uncommon thing to happen as long as we avoided knots to stay on the rope.
I also flew for a few years in western Canada, where dropping the rope seemed to be the standard, even in fairly remote places where it was easy not to hit anything.

I have seen glider clubs do both.  My preference is toward dropping the tow rope prior to touchdown, then having a recovery crew bring it back to the launch site in order to prevent abrasion and or grinding debris into the fibers causing structural damage.  It also prevents damage to the line or the aircraft in the event the rope snags obstructions during rollout.  Conversely, leaving the tow line attached does facilitate quicker turnaround time for the towplane allowing for multiple glider launches in minimal time.

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What happens when an aircraft breaks the sound barrier?
What happens when an aircraft breaks the sound barrier? Why can't it break the sound barrier near the ground?

for the second part it's simple; drag, denser air means more drag to overcome (and regulations about where they are allowed to be faster than sound)

are you asking in terms of physics, or regulations?

Both physics and regulations

The expression "sound barrier" was created maybe 70 years ago when approaching the speed of sound made aircraft react in unanticipated ways. Actually, there is no fixed barrier, and in reality the transition can be rather smooth, provided the aircraft and its pilot are prepared for it.
The speed of sound is the maximum speed with which small pressure changes will propagate through a medium, so at subsonic speed the air ahead of the aircraft can react to the approaching aircraft. Also, while local air density changes only little at subsonic speed, air density changes become dominant at supersonic speed. To make way for an approaching aircraft, subsonic air will speed up while supersonic air will slow down so that density increases to make way for the supersonic aircraft.
At subsonic speed, pressure and speed will change smoothly while air flows around the aircraft. As a consequence, the center of local pressure changes (its lift force) acts at around one quarter of chord, such that the aircraft is balanced when its center of gravity is at the same location.
At supersonic speeds, the air will be taken by surprise - at one moment all was calm and quiet, and suddenly the air molecules get kicked around by an unknown intruder. Pressure changes suddenly, through a shock, so instead of a smooth transition, at supersonic speed there are regions of similar pressure, separated by sudden drops or jumps. As a consequence, the center of pressure changes shifts backwards to 50% of chord. If the center of gravity remains at a quarter chord, the consequence is a strong pitch-down moment: The aircraft will nosedive.
To make matters worse, a control surface deflection, which could redistribute the lift between wing and tail surface, will not necessarily work in the same way as it would at subsonic speed: the aircraft might become uncontrollable. See this answer for a mode detailed explanation.

The cone you see in the right picture is a Mach cone, which would be caused by a supersonic aircraft. The picture was shamelessly copied from this blog.
The trick is now to give the air some advance warning where it counts, even when the aircraft travels at supersonic speed. This can be achieved with wing sweep, because if the sweep angle is larger than the cone angle in which pressure changes will propagate at supersonic flight speed, the air flowing over the wing will be forewarned, thus reacting similarly to subsonic flow. To correct for the inevitable shift in the center of pressure, the tail surfaces are bigger and full-flying in supersonic aircraft, so they work in trans- and supersonic flow. Also, by pumping fuel, the center of gravity can be shifted backwards, so less trim change is needed.
The sound barrier can be broken at any altitude, if the aircraft has a sufficiently powerful engine and is stiff enough. Normally, to save weight, the designers set a limit for maximum dynamic pressure (= air density times air speed squared, divided by two), so the structural deformation at this maximum dynamic pressure is small enough. Note that the deflection of its ailerons will deform the wing of the Eurofighter at maximum dynamic pressure to an extent that three quarters of aileron effectiveness is lost - the ailerons cause a twisting moment which warps the wing such that it works like the wing warping mechanism in the Wright Flyer, only in opposite direction to the aileron input.
Since density drops with increasing altitude, the same dynamic pressure is reached at higher speed, allowing aircraft to fly faster the higher they fly. The next limit is given by the local heat near the stagnation line. If air is decelerated, its temperature will increase with the square of the speed difference. The maximum continuous speed of the F-22 was reduced from Mach 1.8 to Mach 1.6 to avoid overheating the sensitive composite wing structure.

That diagram is fantastic for explaining this phenomenon!

This is a rather broad question, so I'll try to keep it brief.  It just so happens that Scientific American covered your question in detail in an article on March 11, 2002.  Although I think the Wikipedia Page does a better job of describing it than the SciAm article, but is more a history.  Union University gets to the meat of it though.  Some of the key things that happen are:

A plane produces sound that radiates out from the plane in all directions. The waves propagating in front of the plane get crowded together by the motion of the plane. As the plane approaches the speed of sound, the sound pressure "waves" pile up on each other compressing the air. The air in front of the plane exerts a force on the plane impeding its motion. As the plane approaches the speed of sound, it approaches this invisible pressure barrier set up by the sound waves just ahead of the plane. The compressed air in front of the plane exerts a much larger than usual force on the plane. There is a noticeable increase in the aerodynamic drag on the plane at this point, hence the notion of breaking through the "sound barrier." When a plane exceeds the speed of sound it is said to be supersonic.
Anything exceeding the speed of sound creates a "sonic boom", not just airplanes. An airplane, a bullet, or the tip of a bullwhip can create this effect; they all produce a crack. This pressure change created by the sonic boom can be quite damaging. In the case of airplanes, shock waves have been known to break windows in buildings.

The most apparent thing that happens is the sonic boom.
A lot of the images you see on the internet of aircraft breaking the sound barrier are really just shockwaves (condensation) that happen before reaching the speed of sound.  Shockwave propagation starts happening before actually going supersonic because of boundary layers and the air having to move out of the way of the aircraft (as I understand it).  But the pictures look really, really cool!

Here is a nice physics book type of discussion on shockwaves: http://physics.info/shock/
And actually, aircraft are perfectly capable of breaking the sound barrier near the ground.  It's just harder as ratchet freak states in his comment, and also there are a lot of rules against it.

Why can't it break the sound barrier near the ground?

Previous answers have not really answered this.
There is a physical limit. When the sonic shockwave hits the ground, it reflects back up. If the plane is flying too low then the nose shock will bounce back up and impact the tail of the aircraft, causing it to lose directional control and crash.
The low-level variants of the Panavia Tornado supersonic multirole warplane were made shorter than was otherwise optimal, so it could fly lower without meeting its own shockwave. This spoiled its aerodynamics and reduced its maximum speed. The higher-altitude ADV variant had a longer fuselage and could fly faster.

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In case of emergency, is it possible (doable) to land a small propeller-driven aircraft on an aircraft carrier?
I was watching the Disney movie Planes with my younger brother, and one of the characters/planes perform a emergency landing on an aircraft carrier.
And that got me thinking...
In case of emergency, is it possible (doable) to land a small propeller-driven aircraft, like a Cessna 350 Corvalis on a military aircraft carrier?

aircraft carrier can setup a catching net when the plane can't use the cables

Better hope the carrier knows you are coming. Post 911, they're really twitchy.

Any info on the turbulence behind the carrier? Being a Cub driver I would be limited more by that than landing distance.

Related: http://aviation.stackexchange.com/questions/3888/can-a-small-plane-be-floated-off-of-an-aircraft-carrier

Are there civilian aircraft carriers?

@RonJohn - not on purpose - although if I was in a small aircraft, over water, and didn't think I could make it back to land I'd be looking to find me a container ship. Bending the plane to land it on something solid sounds a lot better than ditching in the drink.

As Lnafziger says, a conventional landing is impossible for anything more than a tiny aircraft STOL aircraft (Carrier 'runway' length: 200m). As you state however, if it was an emergency, the aircraft carrier has a special net which it can fold up to stop planes, and since it can stop an F18 Hornet, it could probably take your Cessna as well :)

The trick would still be hitting that relatively low net without being too high. If you were to catch just your landing gear in the net, you would still probably stop but the results wouldn't be pretty.

Do you consider a C-130 Hercules "a tiny aircraft"?

@GregHewgill: The trick is hitting the net with wheels firmly on the deck. Notice the puff of smoke on the second frame of the included animation indicating that the aircraft actually touched down long before the net.

I wonder what the propeller would do to that net??  :-)

I just noticed the F18 landing above also used the tailhook.

@GregHewgill i think the problem here was that the gear was not locked, no problem with  the tailhook

@GregHewgill That's not an F-18, that's an A-6.

@Livius: Sorry, I was just going by what the OP said.

@Manfred: What I meant was that the net wasn't the only thing stopping the aircraft, since the tailhook was used too.

Um, guys, isn't that an S-3 Viking?

@FredLarson -- yeah, you're right. But at least an A-6 looks vaguley similar to an S-3 (not like an F-18!). :-)

@Livius: Yeah, mistaking it for an F-18 really blows my mind.

I realise the question is whether we can land the plane, not whether we can walk away, but out of interest: is the stuff attaching us to our seats in our "small propeller-driven aircraft" rated for the Gs we'll pull when we hit that net? I guess it depends quite a lot on our stall speed? Would be a shame to land nicely but need scraping off the inside of the windshield.

@SteveJessop: The belts should be rated to enough to prevent you from hitting things in any survivable crash. Even the two-point passenger belts in airliners should handle at least 9G, so the 3 or 5-point belts should handle more. The net generates far less.

@Lnafziger nothing... The net is made of sturdier stuff. The prop'd get tangled in it, possibly torn off or seriously damaged.

@MikeFoxtrot You would rip your aircraft apart and probably kill the occupants if you tried a barricade arrestment in a small aircraft.  The barricade is rated to stop much heavier, faster aircraft with much sturdier fuselages.  The net probably wouldn't pay out very much and the aircraft would come to a smashing stop as if hitting a wall.

@GregHewgill rather ask what the net would do to the prop. It's not hemp rope, it's steel cables. A wood or fiberglass prop would simply be shredded to bits, a metal prop severely damaged. Let's put it like this: if you're caught in that net you're not going to fly off that deck.

This answer doesn't take into account wind speed or the speed of the carrier, both of which are very important for all aircraft, and make it possible to land an aircraft without a hook, whose normal landing distance is greater than the length of the carrier.

A South Vietnamese Air Force Cessna O-1 landed on the USS Midway at the end of the Vietnam War. Fixed-wing VNAF aircraft usually flew to Thailand, and the naval evacuation was carried out by helicopter (with crews sometimes ditching in the water after the flight decks ran out of room), but this O-1 pilot wound up making his first carrier landing, with his family on board and an hour of fuel left.
Wikipedia wrote a paragraph about it and has another couple photos.

To be fair, O-1 was technically a STOL aircraft used for military observation. It could land in a parking lot.

@TechZen true, but it was a small prop aircraft :) If the carrier is going at its regular speed for landing operations, something like a C.172 would if it slowed to stall speed only be going something like 10 knots faster than the speed of the ship. Doesn't take much to stop then :)

Yeah that's the important factor - a C172 or similar stalls at around 47 knots. An aircraft carrier can travel at 30+ knots, so even assuming there's no wind (which would be a headwind assuming that carrier turned into it as normal) the plane is only travelling at a relative 17kts. Stopping from 17kts in 300ft isn't outrageous. A skilled pilot could even potentially climb from slightly below deck level and stall onto the deck, travelling even slower. With even a moderate 30kt headwind, you could actually allow the carrier to overtake you and land backwards...

@JonStory: Great, now I have to get that particular picture out of my mind. "Hey carrier, would you mind catching up a bit?"

I've got to be honest, I'm incredibly tempted to steal a C172 and a Nimitz Class Carrier and try that now.... who's up for a day trip?

This should be accepted answer.  The question was "is it possible" and the answer contains proof.

@TechZen - well, technically a runway is just a special kind of parking lot. :-)

A light aircraft (e.g. C172) has a landing roll of around 500 feet. There are no 50 foot obstacles to consider so the 1500 foot to a 50 foot obstacle isn't required. Thats from 60 knots to a full stop. Going from 60 knots to 30 knots (30 knots is the wind over the deck) means it will be less than half that.
So the problem is not one of the aircraft, most light aircraft with similar performance are perfectly capable of doing it without a landing hook or anything like that. The problem is the pilot, with no training or practice this will be very hard to do because the deck is moving in the swell, and its also moving sideways due to the angled deck. A bad crash is the most likely outcome.
An ex navy pilot with recent experience. Now thats a different story, even without arrestor hook etc etc they would find it easy compared to landing their big heavy jet on the deck.
The Corvalis is a hot ship in light aircraft terms with a much longer ground roll, so this would be tight. Again with skill (ex navy pilot etc etc) and wind over the deck (you can get going on 30 knots from the ship even if the wind is calm) I think it could still be done.

Just like to add, with the carrier doing 30 knots into a 20 knot headwind, that would be 50 knots over the deck, making a 172 landing very easy only having to lose 10 knots of speed... for an experienced pilot. I am not navy trained, and I wouldn't like to try it no matter how much money you paid me. Would I ditch rather than land on a carrier? Dunno. I'm not in that situation right now so its really hard to tell. Also in that situation the 172 might not want to stay on the deck as the stall speed would be less than the 50 knot wind over the deck.

While experience helps, I have some reservations that an experienced navy pilot will find it easy to land a Cessna on the deck. Carrier landing is performed without flare: they just aim at a point and smash the aircraft there (with the navy aircraft having reinforced landing gear). A Cessna, even despite much lower approach speed, may not hold the impact if landed this way. Doing a flare is also not easy due to deck movement (except in a calmest sea), even if distance allows. Another factor is the airwake turbulence, to which a light aircraft will be more sensitive and exposed for longer time.

“Going from 60 knots to 30 knots (30 knots is the wind over the deck) means it will be less than half that.” — from 60 to 30 it is ¾ of distance of 60 to 0. Fortunately, in the reference frame of the deck it is 30 to 0 and that is only ¼ distance.

I'd just like to add, in the early 1940's, many propeller driven aircraft took off and landed from aircraft carriers... because... jets were not operational until later that decade. In some instances without hooks. Also its definitely a great help for any aircraft having the carrier steaming at 30 knots into wind, making for more than 30 knots over the deck. If the wind was zero and the carrier in port, it would be much harder, to the point that any aeroplane apart from maybe a microlight would be able to take off or land at all.

@Zeus: If you think the landing gear of a 172 is weak, you might want to check this video: https://youtu.be/Kx5YeqTBcDI

The published landing distance for the Cessna is the certified distance - that's what it needs in a worst-case, no-flaps, high, hot, zero-wind landing. Any pilot will tell you that they rarely need the whole runway.
Consider the big picture of the aircraft carrier. The ocean is HUGE (ask the people searching for Malaysia 370) and rather featureless. Private planes rarely cross large paths of open ocean as it's often the longest route to where they are going rather than the shortest. So the chances of a carrier battle group being anywhere near you are extremely small. If your plane is flying well enough to find the CBG, come in behind and line up for a landing then you probably don't need it in the first place.
In theory, light aircraft would have no technical problems landing on the deck. Lots of room with a 30-50kt headwind, no need for a tailhook or nets as you don't weigh 30,000 pounds or come in at 200kt IAS on full afterburner. The chances of a non-navy-trained pilot hitting the touchdown zone of a runway moving away from them at 30kt and pitching up and down several meters is laughably small. You would either miss and have to go around (again, if you can do that, you don't need the carrier in the first place) or make a mess on the fantail. Even navy pilots do this on occasion, but they have ejection seats.

Note to editor: "full afterburner" is a lot more than 200 kts!". No, it isn't. Full afterburner is a thrust level. You can run the 'burner all the way up standing still. Carrier aircraft always land at full power in case they miss the cable, but the cable needs to be stronger to stop both the kinetic energy of the plane and the engine thrust.

It's more accurate to say that they go to full power with afterburners at about the point the wheels hit the deck (in order to give the engines their 4-5 seconds to spool up if they miss the cables shortly after touchdown); approach is not, as far as I'm aware, done at anything like full throttle.

The question was clear.  This is an "is it physically possible" question not "is it likely."

@NathanTuggy, it is more accurate to say they go mil (= full dry) power, without afterburners, at about the point the wheels hit the deck.

In a 20 knot headwind and with the ship making 30 knots a Cessna 172 could hover over the deck of a carrier, choosing a "comfy" spot to try to set her down. Remember a ship is moving up and down, twisting side to side, yawing, pitching, and more. The heavier the seas the more movement you have. With a slight headwind a pilot could land a 172 on a carrier deck that was still in port. C130 only needed 270 feet while the ship was underway, so a C172 wouldn't need more.
STOL aircraft could fly backwards from the bow to the Stern. Having flown in 45 knot winds at really slow speeds, it appeared to people on the ground that I was flying my aircraft backwards as my ground speed reached negative numbers. STOL aircraft land in really short distances - some as little as 27 feet.

In theory, yes it is possible to do so.  It all depends on the aircraft type, approach speeds, sea and weather conditions, etc.
During the end of the Vietnam War, a South Vietnamsee refugee landed an OV-1 Bird Dog on the deck of the USS Midway (CV-41).  So, yes light airplanes have made unarrested landings on carriers in the past.  If your in a light airplane with a stall speed around 30kts and very proficient on your short field landings, this should be no sweat, provided the ship can steam either at, or into the prevailing wind at 30 or so kts.  If you're flying a dedicated bush airplane eg an Aviat Husky, Carbon Cub, etc designed for STOL operations, it may even be possible to stick a 3-wire (touch down and hold the main wheels in the third cross deck pendant full stop) under these conditions.
Larger, heavier aircraft have faster approach speeds and need considerably more runway to stop on.  The CE-350 Corvalis mentioned above is going to require around 1500-2000 ft to land depending on ambient atmospheric conditions at sea level and calm winds, provided you can fly a short field right by the book.  Even with a 30kt headwind, you're looking at an 1100 ft or so of ground roll, making an unarrested landing on a carrier impractical.
If there was no other option available to you, the deck hands could rig the barricade - a device which looks something like a tennis court net on steroids.  Granted this device was designed to stop aircraft 10-20 times the weight of a Corvalis at nearly twice the approach speed and I don't know if the arresting gear attached to it have settings available for smaller lighter aircraft.  If it doesn't, it could cause serious structural damage to your airplane, possibly making things worse.  Maybe that's better than ditching alongside the ship, maybe not.
Another factor would be the sea itself.  Carriers are not fixed airfields and in rough seas, the deck lists, pitches, and rolls considerably - think of a 100,000 ton cork bobbing in the ocean - making approaches quite dangerous for neophyte pilots.  Rough swellscouldbreak the gear off or do other structural damage during a round out, or cause the pilot to strike the round out, etc.  but if there was no other alternative, it's a risk you would have to take.

Hmm, it seems like everything you answer says is already addressed by the other answers.

According to this page, the landing distance of the Cessna 350 is 2,350 feet.
A Nimitz class carrier deck is close to 1,000 feet long, and can travel about 30 knots. If they were going full speed into a headwind, it might be possible for them to stop in time, but it would be pretty scary, and if they ran off the end they would be run over by the carrier!
Note however that the airplane would pretty much have to be directly above it when it happened, and I doubt that the military would like a civilian aircraft being that close in the first place so it's very unlikely to ever even be an option unless it was setup in advance.
A different airplane like a Super Cub or as you pointed out a C-130, which can land in about 300 feet could do it pretty easily, even without the wind as long as they don't get caught up in the arresting gear.

According to http://www.pilotfriend.com/aircraft%20performance/columbia/2.htm, the 350 has a no-wind landing ground run of 1550 feet and a landing stall speed of 57 knots.  Steaming at 30 knots doubles the effective length of the carrier, so landing without arresting gear would be quite possible; with the carrier steaming into a stiff headwind, you could actually fly a "vertical" landing.

@lnafziger run over by the carrier is less likely due to the fact that u land on the angled deck rather than the straight deck. You are more likely to fall over board :)

@Mark: You are underestimating the effect. Grossly!

Ok, so let's take the 2350 ft distance and 74 (1.3 * 57) knots Vref and no wind. The motion of the carrier redues the speed to just 44 knots and since the landing distance is proportional to square of speed, that leaves us with 831 ft, well within the available 1000. Of course it's still rather risky since there is no runway overrun area (aircraft with arrestor gear actually apply full power just before touch-down, so they can touch-and-go if they miss the arrestor), but in an emergency doable.

There are plenty of small propeller-driven planes with landing distances well below 1000 feet. Even not so tiny ones, like the AN-2 can land in about 700 feet.

@vsz I agree, and mention two in my answer, and definitely the C-130 falls into the "not so tiny" category.   He specifically asked about that airplane though.

@JanHudec Looks good,  I didn't know the approach speed when I wrote my answer. Still not a lot of room for error though, and this assumes that the carrier is actually going full speed.

@JanHudec I also wonder how far down the runway that you would have to land to avoid the arresting wires...

@Lnafziger: I don't think you'd have to avoid them. They are only about an inch above the surface and wheels just run over them. In almost any regular landing on the deck the main wheels will run over one or two last wires.

@JanHudec cool!

@Lnafziger: That's why carrier planes need tailhooks to catch the wires.

An aircraft with a grappling hook could do it such as a Cessna which is capable of towing a banner. It wouldn't end well, but he could survive for sure. A Cessna 172 needs about 1,500 feet of runway for landing... depending on fuel load of course. Typical carrier landing zone is only about 1,000 feet. The grappling hook used to load a banner could reduce the inertia enough that the plane would not explode if it caught a landing wire, but I would not recommend it... it'd rip the plane apart. 'Traps' are practiced on land before on sea. It would be very difficult for a Cessna to capture the 'meatball' for an inexperienced pilot on an angle deck. Your runway is constantly drifting right.
The VS0 of a Cessna 172 (Down and dirty) is 54Mph, an Aircraft Carrier can easily do 46Mph if turned into the wind. A reduction of 8Mph within 1,000 feet is not impossible... so yes, it's possible.

I suppose if it were an emergency (Not like torn radio aerial, more like fuel
leaking/low in the middle of the ocean) you could save yourself by ditching
the plane, parachuting onto the aircraft carrier.  You'd be arrested by armed
navy men, but as long as you don't try to fight back, you'll be taken to
wherever they're going in the brig - alive. (And not drowned, marooned, or eaten
by sharks)  This of course would be after you beg over the radio to land.
If they say yes, you can save your plane, maybe buy some of their fuel, and
take off for wherever you're going (or be arrested with your plane, get taken
to wherever they're going, and pay for a hangar there while you figure things out.
Not sure what navy protocol on this is.

I imagine policy is "sorry, no" because of what paul said in his answer, particularly the part about likely crashing on their carrier.

What's the 100LL rate on a carrier these days. Is it self serve and do they take Amex?

authors: Bob Jarvis - Слава Україні


text:
Do commercial airlines have procedures for evacuating pets from the cabin in an emergency?
I recently got into an offsite discussion about flying with pets in the cabin and what would happen in an emergency on board. I brought up the fact that United Airlines' pet policy states, "In the event of an emergency, oxygen service will not be available for pets." Southwest has a similar phrase in their pet policy, though I couldn't find anything similar in American Airlines' or Delta's pet policies.
Beyond oxygen service, I was arguing that if an evacuation took place, I wasn't aware of any procedures for getting a carryon pet evacuated safely. I said that the human lives of the other passengers on board would take precedence over a pet. To my knowledge, pets in carriers are essentially treated as a carryon bags in the cabin. I also hypothesized that letting a pet out during an emergency could be extremely dangerous and would likely invoke the ire of the crew, if not get you into legal trouble.
TL/DR: The discussion left me wondering are there actually any procedures for getting carryon pets out of the cabin in an emergency? This is mostly directed at pets that would be in a small kennel and stowed for the duration of the flight under the seat in front of you as a personal item. Are they considered carryon luggage, which should then remain stowed (as awful as that sounds), or treated like infants? Have there been instances of serious accidents where carryon pets were also evacuated in the past?

I'm more interested in animals that aren't service animals, since I know that service animals are governed by different regulations. Cargo hold didn't come up in the discussion, so I'm mostly curiously about pets brought aboard in a small carrier and stowed as the personal item under the seat in front of you.

There are no policies because pets are technically cargo/baggage as you note in the question, and treated as such. In other words in case of an emergency evacuating the passengers is a priority and as you would be instructed to leave your baggage behind you would more than likely be instructed to leave any pets behind.

The Federal Aviation Administration (FAA) allows each airline to
  decide if they will allow you to travel with your pet in the passenger
  cabin. If an airline does allow you to bring your pet into the cabin,
  we consider your pet container to be carry-on baggage and you must
  follow all carry on baggage rules (14 CFR part 121, section
  121.589)

The exception to this is service animals which are not treated as pets.

Service animals are not pets. They are working animals that assist persons with disabilities.


text:
Where to relocate a bomb on a plane to minimize damage?
In a video blog I saw today on the net, an airline Captain said: "if a bomb is found on board in-flight, pilots are trained to relocate it someplace where it would do the least damage" without further details as to what place standard operating procedures suggest in this case.
Where should the pilot put the bomb to have the best chances of limiting the detonation damage and rescuing the plane ?

I am very relieved that you're not asking where to put a bomb so as to maximize damage.

Maybe the centre of the cabin as it should be stronger because of the wing joint with the fuselage? But I am not, sure

Have to go with out the window on this one.  In a safe drop area of course.

@TannerSwett I'm sure the NSA is watching this thread now anyway

We covered that stuff during recurrent training and for the CRJ Regional Jets we were told to place it in the forward galley in front of the service door (opposite the main door) and cover with with as much weighty stuff as possible, wet blankets, heavy coats, and such.
You had the mass of the galley to protect the flight deck to some degree, and in theory the explosion would blow out the service door, hopefully leaving the structural frame surround intact, so that overall, it would have the least impact structurally for the fuselage as a load bearing tube with the peak stress just ahead and behind the wings.
In theory... nobody actually believed it would save the plane unless it was fairly small device, but as a calculated strategy to make the best of a hopeless situation, it made sense.
Don't know about other jets, but I would expect that the overall logic is similar.

thank you. There have actually been a number of incidents with small, improvised devices, so I do think that training might actually be helpful!

Why do not you throw it out of the plane after descending low enough to make possible to open something like window in the cockpit?

That's actually not a crazy idea; if you descended to a safe altitude and depressurized, and slowed down to approach speed, you could remove an overwing escape hatch (impossible when pressurized), which comes off into the interior, and pitch it out.  With tail engines, I would shut down the engine on that side as a precaution.  You might even be able to get the hatch back in place.

If there were double doors as on a submarine it would not be necessary to depressurize the entire cabin.  Maybe something could be built into the restroom of the next Boeing rendition.

@h22 -- it is indeed not a crazy idea, depending on your plane.  Gulfstream's procedures for their bizjets use the baggage door for this consideration (as there are some special mission Gulfstreams that are designed to drop things out the baggage compartment door).


text:
Are glider winch launches rarer in the USA than in the rest of the world? Why?
I had heard before that winch-launching gliders was a relatively rare practice in the USA, while quite common in the rest of the world.
My data is mostly anecdotal, but I do know gliding clubs in Europe that exclusively use winches.
A recent post in The Hangar reminded me of this: Tanner claims their club owns the first winch launcher sold by Tost to a USA customer, and that they have not used it in years.
As far as I know general aviation scene in the Asia-Pacific region takes after that in the US, but I have no concrete knowledge.
Is winch launching relatively rarer in the USA than in the rest of the world? If so, why? How does it compare to other regions?

I'm curious about your source for "rest of the world".

It is in the next sentence, anecdotal data mostly, hence the question itself.

@AEhere Europe != "the rest of the world." The world consists of more than just Europe and the USA. :)

@reirab did I somehow conflate them? I said I had heard they were less common in the USA and had anecdotal data for the EU. Where did you read the EU == rest of the world equivalence?

@AEhere Your question is about USA vs. "the rest of the world," but your anecdotal data is only for the USA and Europe. It seems like the question is more like, "Why are winch launches less common in the USA than in the EU?" to which the answer is mostly, "Because most (if not all) EU countries have very high fuel taxes, leading to pump prices almost 4x what they are in the USA."

@reirab is it clearer now?

If you find a place in the United States that does ground launch let me know. I'm a glider pilot and it would be fun to get the endorsement to do that but I'm not aware of any place in the United States that does that. Here is 1/2 self-launch and 1/2 aero tow.

To expand on Quiet Flyer's answer, it's technical and economic at the same time.
Technical: Winch is limiting because you are deposited in the same spot over the field, whereas a tow, if the pilot knows what he's doing, can take you to a thermal up to a few miles from the field.  Plus you can get towed higher.  If you had to choose the launch method that gives the highest probability for a successful flight, aerotow's a no-brainer.
Economic: Because of the higher average individual purchasing power in the US (and Canada to more or less the same degree) of disposable income (for example, power flying is a middle class, even lower middle class, activity in the US and Canada, and an upper middle class activity in EU), glider pilots can afford the higher cost of a tow, but which is still cheaper than a tow in Europe because overall operating costs for power planes are less.
So given the choice between paying 15-20 bucks for a winch launch to hopefully 2000 ft (if you have a runway long enough to fit the cable) and 30-40 bucks to be hauled to 3000 feet in a Pawnee, whose pilot, if reasonably skilled, will find and drop you off right at a thermal, most North American glider pilots will pay the 30-40 for the tow.
So the result is there is very little market demand for winch operations in North America, except with some small clubs in out of the way places without the money and resources to run a tow plane.

The one thing I'd say is that winch launches in the EU can be very, very cheap in comparison. One club I've glided from repeatedly has an electric winch that you can easily pull 1000 ft from, often into a thermal. If not, you practice a circuit and try again. The price in USD is about $6-8.

Interesting.   I'd probably go for that just for the thrill of the low cost kite ride.  What is the typical charge for a launch to say 1.5 to 2k with a gas powered winch?  I was just guessing at 15-20$.

@Landak to supplement John's question, I'd also be interested if you could provide data on the cost of a tow in the EU.

@JohnK -- it's really the length of the runway that gets limiting for height, not particularly the motor on the other end. Again, most clubs I've been to have a fixed fee per launch, typically with member vs non-member discounts, but not depending on how hard you pull.
A ballpark figure for a 2000 ft aerotow is ~$40 USD (most places have a set price per thousand feet).
I personally prefer winch launches - on tow there is a period where you are low and slow, and, depending on geography, might not have a good option to land ahead if required - this doesn't really happen on a winch.

Also, http://www.startwinde.de/ -- this German (electric) winch manufacturer's website states on the financing ("finanzierung") page that the approximate cost per launch varies between €1,80 and €3,51 (depending on how many you do a year) with a large chunk of the cost being electricity.

Wow, $15 for a winch launch? No wonder it's unpopular (I guess it's expensive because it's unpopular). Here in Europe (NL, CZ), it's around €4 for a winch launch, compared to a tow for ~ €15-20 (or often €30+ if you're not a member). I'd expect towing to be quite expensive in the US because you have to pay an appropriately certificated pilot to spend all day doing relatively boring work, and even in Czechia where labor is really cheap a tow is around €4 per minute (and you need at least 4 minutes to get anywhere).

In NA there are a few commercial soaring centres around, especially in the US, but most are non-profit private clubs, and the towing is done by private pilot club members, so the tow fee reflects just the operating costs of the tug.  Winch launches at 4-6 euros seems pretty attractive, and if my club had a winch option that would get me to 2000 ft for under 10 bucks, I'd probably go for that, but most pilots here would prefer to pay for the tow.  Maybe "disposable" income for the average glider pilot is a bigger factor so in NA most don't mind paying extra to be taken to lift.

Many of the towing pilots in the UK are paid to cut the grass etc as they are not licensed to charge for being a pilot.   They are doing it to build up hours.

Is winch launching relatively rarer in the USA than in the rest of the
  world?

Definitely.

If so, why?

At least in part because airplane fuel, as well as some other costs associated with powered aviation, are cheaper in the US than in many other countries.

Future edit-- harmonize grammar

Source about "rest of the world"? In Argentina, where I flew the most, winch tows are extremely rare (say, 1% of the clubs or something like that, and I don't think there's a single winch-only operation).

@MartinArgerami -- still, if you averaged the rate of aerotow to winch tow launches in US versus the whole global average, it would be higher in the US. Interesting to point out other exceptions though. How about, say, South Africa?

Just noticed my answer could be interpreted along the lines of "glider flying is rare in the US because it's not too expensive to  fly power planes, so people do that instead".  That was not my intention!  Any enlightened person would prefer to go soaring rather than drilling holes in the sky with an airplane, whenever weather conditions and circumstances permit.

Sure, unless that enlightened person wanted to fly to a powered-aircraft only airport for lunch with a couple of passengers, or for an afternoon golf outing. Or for any other reason that has to with flying to actually get somewhere vs just flying around to see what the birds are doing.  I'm that's an old argument tho.

This is strongly influenced by the overwhelming number of airports in the United States compared to other countries.
According to chartsbin, which pulled it's data from the CIA world factbook, in 2010 there were 43,982 airports in the world, of which 34 percent (15079) are in the United States.
The US also tops the world in unpaved airfields with 9,885.  The next highest country on that list was Brazil with 3346 and only Mexico in the group topping 1000.
Couple all of this with the US accounting for less than 5 percent of the world population and one thing becomes clear...there are just a lot more places to aerotow from in the US than the rest of the world.
I would guess (will try to backup with stats later) that the US also accounts for a much bigger proportion of GA (and thus tow capable) airplanes as well.
As an aside, so far all of my 150+ glider flights have been aerotow.  I look forward at some point to try winch launching...I've heard it is quite a rush!

"I've heard it is quite a rush!" Especially if you break a tow link at low altitude...

There are 416k GA airplanes in the world, and 220k of them (52.9%) are registered in the US. Data for pilots is harder to come by, but it is likely similar.

@StephenS thanks...do you mind if I add that to my answer?

@bclarkreston Sure, though you should source it.
I think I read that in a GAMA report linked in another answer here.

We (Sutton Bank, UK) only winch launch on our short rwy 24 when there's sufficient wind for ridge lift to work on the cliff at the end of said rwy 24. Typical launch height is 400'-500', and the winch is made out of old combine harvester parts with an enormous Cummins 6 pot diesel engine. All but the very lowest of cable breaks result in a normal flight, because landing ahead generally isn't possible. So if it's quite a rush you're looking for...

@TobyWilson " made out of old combine harvester parts with an enormous Cummins 6 pot diesel engine" Huh, I always thought the Mad Max universe was set in Australia, not elsewhere in the Commonwealth.

Watching YouTube videos like this one, I get the impression that car towing is quite popular in the USA - especially for instruction flights.
The reason why car towing is done instead of winch launching is simple:
Car towing is quite simple: You require a powerful SUV that you can buy at the next car dealer.
Winch launching requires a winch. I have read that a winch costs more than 300 thousand EUR (350 thousand USD). Because of this high price most clubs here in Germany try to build their winches themselves and sometimes fail due to the lack of engineering skills. (Years ago I myself was a member of a club who failed.)
So if you have the choice between winch launch and car towing, you will probably decide to do car towing.
However, here in Germany car towing is nearly never done because of the airfield sizes:
Using a winch a runway length of 950m is sufficient to lift a glider to 1100ft GND. I have read that a runway length of 1700m is enough for 2000ft GND. The runway length of 2000m in the YouTube video was only sufficient for 700ft GND using car towing.
This means that car towing requires much longer runways than winch launching.
A typical airfield here in Germany has a runway length of 600m, however, winch launching is only done on airfields with runway lengths of 800m and longer.
Europe is rather densely populated so there is simply no space left to build (general aviation) airfields with longer runways.

Good points- on the whole I'd say car towing is much less common then aerotow in the US, but I have participated in it, and I've never even seen a winch, at least in the sailplane context.

Thanks for bringing up the competing alternative of car towing, I did not consider it.

The FAA's Glider Flying Handbook says that "Automobile launches today are very rare," which led me to believe they're probably the least popular method of launching nowadays. (Glider Flying Handbook 2013, FAA-H-8083-13A, page 7-14.) I've never heard of a car launch happening anywhere near where my club operates (69G Richmond Field in southeastern Michigan). For what it's worth, our runway is about 2400 feet (800 m).


text:
How does turning a small plane by opening the doors work?
I've just watched a video of a small Cessna turning not with ailerons or rudder but by opening its doors. They said that the door acts like a rudder, but in the video one of the guys opens the left door and the airplane rolls right. That doesn't  make too much sense to me...
I've been searching on the internet and I found a different explanation which  stated that the airflow stacks up below the wing because of the door and then an over-pressure is exerted making the airplane roll into the opposite direction, in this case to the right (which is what can be seen on the video). Can anyone confirm this second explanation?
And if I wanted to roll a Piper or any other low-wing aircraft by using the doors, what would the airflow's behaviour be?

Can you put in a link to the video?

A lot of low wing Pipers, like the Cherokee, only have one door.

ProTip: I'd use the aileron to roll the piper.

The second explanation is right. The blocking effect of the door below the wing will force more air above it, so suction and lift above get higher. Of course, the blocking effect will also increase pressure locally on the lower side of the wing.
If you do the same on a low wing aircraft, it will roll to the opposite direction. Now the door acts like a spoiler and reduces lift.
Generally, such a one-sided creation of a disturbance will upset the aircraft and will make it roll and yaw in an uncoordinated manner. And the "rudder" explanation is wrong - a rudder creates a sideforce at a distance to the center of gravity, while the door is pretty much where the pilots and the center of gravity are. The better explanation would say that the door acts like a spoiler, and those are used routinely for roll control:

in airliners
in unmanned vehicles

Well kind of it acts like a rudder.  It really is more of a differential airbrake, creating asymmetrical parasite drag about the vertical axis of the aircraft and inducing a yawing moment, turning the longitudinal direction of the aircraft to the left or the right of its current path of motion.  The thrust from the propeller then creates a lateral component of thrust, turning the aircraft.

very good answer!  I suspect it may be both what you said and what @Tyler Durden said combined...

Only small addition. I believe as KorvinStarmast has pointed out below, the door works as a spoiler. It creates form drag by separating the flow. (not parasite drag) and yaw-roll coupling via dihedral is the mechanism which should be responsible for creating rolling moment.( not propeller thrust)

Form drag is parasite drag.

Also, it might be because of the weight balance, allowing it to "tilt" to one side.

An open door in flight on a high-wing aircraft will act like a flap. It will increase the drag on that side, both vertical and horizontal. The aircraft will slow down and the increase in surface area on the left will cause the right side to drop. It depends of course on the type of door and aircraft. On a low-wing craft, opening a door will just increase the drag since the vertical presentation will be unchanged.

How does it act like a flap? Flaps deflect air downwards; doors deflect air sideways. Why does greater surface area on one side cause the other side to drop?

@Richerby Even though the door is mostly vertical, due to turbulence effects it increases the effective surface area on that side of the aircraft (assuming it is a high-wing aircraft).

"Acts like a spoiler" would be more accurate than "acts like a flap" since a flap gives you lift, and the door does not.

Spoilers generally only increase the drag, not the surface area of the wing.

please, show me how a door can increase the surface area of a wing, I'm intrigued.

Spoilers generally only increase the drag Likewise with doors. Heck, even the landing gear doors increase drag while they are open.  I am trying to help you improve your answer, Tyler.


text:
Could clouds on aircraft wings produce lightning?
As air is accelerated over the wing, pressure drops and so does temperature, which is reduced to dew point and finally a cloud forms, which can be seen on humid days. My question is, can this cloud formed over the wing of an airplane produce lightning activity just like some other kinds of "normal clouds"?

For a cloud to produce lightning, it needs to be charged, and as clouds don't form over aircraft wings, it can't attract lightning activity, or be charged.

Normal clouds do not produce lightning. Only cumulonimbus clouds.

@J.Hougaard Surely that can't be right?  I've frequently seen lightning produced simply through the effect of heavy rain fall from clouds that would be better classified as nimbostratus.

@Michael That is one of the very first things you well learn in any meteorology course. What you have probably seen is a cumulonimbus embedded in other stratiform clouds.

Lightning occurs when an electrical charge is built up within a cloud, due to static electricity generated by supercooled water droplets colliding with ice crystals near the freezing level. When a large enough charge is built up, a large discharge will occur and can be seen as lightning (from Wikipedia).
So you need two things for lightning to occur- a charge buildup in a place and a charge gradient (difference in charge, like between two clouds or cloud to surface) for lightning to occur.
Based on this, there is little chance of any charge buildup and discharge in the condensation over wings- it is too short lived for any charge buildup within itself and the charges over the aircraft wings are  dissipated by the static wicks in the trailing edges- so no chance of 'cloud' to wing surface either.

Don't helicopters build up enough of a static charge to shock people though?  And that's an airfoil...  To be fair, that's not technically lightning (an arc that goes between a cloud and either the ground or another cloud), and as I recall it's just the blade passing through the air, with or without moisture.  So I guess that's not what we are looking for, eh?

@JayCarr you are correct. All aircraft can build up a static charge if not designed correctly. As the answer says, fixed wings have wicks to dissipate this charge. I would assume and think it highly likely rotary aircraft have similar mechanisms.

@JayCarr, the static wicks don't eliminate the resistence, only reduce it, and they can only equalise the charge towards the ambient potential. Therefore as the aircraft—fixed wing, rotorcraft or aerostat (it was static discharge that set the Hindenburg on fire)—flies near or through a storm, it will collect charge and some will still be there upon landing. Normally it will discharge through the landing gear; only when attaching or detaching under-slung cargo to a helicopter (and when tieing an aerostat) can there be a problem. Either way it requires already charged air though.

@JanHudec Ah, and now I understand that one scene from "The Hunt for Red October" when they were trying to collect Jack Ryan from a helicopter to a submarine....  Thanks!

Friction creates static electricity
On the principle you're right: Electrons are separated from air or water vapor molecules due to friction occurring in the boundary layer and other friction areas. Instantaneously there are two types of static electricity created: Negative where some ripped off electrons are located and positive where air molecules with a missing electron are located (these molecules are named "ions" to indicate their electronic unbalance).

Ions are naturally neutralized
However opposite charges are attracted to each other, the ions recombine soon with their separated electrons behind the aircraft, the number of isolated ions or electrons –the "electric potential"– at any time doesn't build up so that a difference of potential with the ground, another mass, or between ions and electrons is sufficient to create any significant electrostatic discharge.
Note the recombination is accelerated by the water in the air, as water –with impurities– is a better conductor of electricity than dry air. Condensation doesn't help for static charge creation on aircraft.
Huge potential differences are required for lightning
The difference of potential is measured in volts*. It requires 3,000 V to initiate an electrostatic breakdown for each millimeter of dry air –the voltage used in an automotive sparking plug is about 10 times this value to ensure a good spark– or 3 GV per km.

Source
If the electrons were trapped on the aircraft surface, the potential of the aircraft would reach the value required to create lightning with the ground :-)
So, why lightning happens with clouds but not with aircraft?
Friction surface from wings is ridiculously small compared to friction surface in the huge cumulonimbus cloud. Static electricity created is not of the same order of magnitude. That's a first reason, but there is also a significant difference in how charges behave.
In natural lightning the electrons and the positive ions are created by the violent wind inside specific clouds. However, contrary to what happens with an aircraft, and for reasons not yet really understood, charged particles are then physically separated: Positive ions move at the top of the cloud while negative charges move at the center where they combine temporary with neutral molecules to form negative ions.
A smaller quantity of positive ions also moves at the bottom. This positive cloud bottom also moves negative charges of the ground at its nadir, which in turn reduces the thickness of the air layer to move through, and at the same time increases the electrical field gradient.

Source
As friction continues in the cloud, the electrical potential increases until the difference of potential between the bottom of the cloud and the ground reaches the voltage threshold required for breakdown. The huge avalanche breakdown heat creates plasma used by particles in excess to join the attractive ground. This phenomena is complex and still not entirely explained either.
*: The volt is the electrical potential required to create one joule of work with a charge of one coulomb. See this nice page for more details.

can this cloud formed over the wing of an airplane produce lightning activity just like some other kinds of "normal clouds"?

No. Lightning requires large, long-lived clouds in which warm, wet air can rise, condense and fall again. That kind of structure can't exist in a cloud so small and temporary as a contrail.
Wikipedia's page on thunderstorms contains lots of information about what's needed.

Thanks for mentioning cloud size. This is the key enabler for lightning.

TL-DR: lightning is made possible not by the availability of free electrons (a very common occurrence, in Nature and in the atmosphere in particular), but by the existence of some non-electric force which separates positive and negative ions (despite their electrostatic attraction), over scales large enough  to give rise to a large, sudden increase in the number of free, energetic electrons, once a threshold value of the electric field is reached. No such forces exist over the surface of a metal.
All of the previous answers are correct, but they touch in passing (and not all of them, at this) on the key prerequisite for the formation of lightning: the maintenance of large-scale charge separation, i.e. on the scale of kilometers.
Ionizing gases is reasonably easy, and all sorts of forces are able the sever the links between the outermost (and least bound) electrons from their (aptly called) donor atoms. But this occurs rather uniformly across an average gas like the Earth's atmosphere, which means that, in any given microscopic volume, there are as many positive as negative ions. The ensuing electric field is nearly vanishing, and achieving the large electric field necessary for a lightning discharge (roughly 3GV per km, as pointed out by mins) is impossible.
For instance, on an airplane wing, which is an excellent conductor, electric forces will tend to keep the positive and the negative (=electrons) ions very close to each other, and no large-scale electric field will ever be produced.
The key to explain lightning is that there are other forces which tend to pull electrons and positive ions apart, over very large distances. This has been stated already by mins (although I believe less clearly), and by David Rickerby. The fact that the nature of these forces is not clearly understood does not detract from the fact that this is what makes lightning  possible.
It is easy to understand why such large electric fields are necessary: an electron hitting a neutral atom can ionize it, thus freeing one more electron which will go on to produce twice more free electrons as our initial situation where we only has an electron. But in ionizing a neutral atom, the original electron will lose energy, and might be unable to ionize an another atom when the next collision occurs, and/or it might produce a new electron which also does not have enough kinetic energy to ionize the next neutral it hits: thus no cascade, thus no increase in the number of electrons, thus no lightning.
Unlesss... the electric field is so strong that it replenishes the energy of the original electron (and of course also of its newly-formed brethren) of enough energy between collisions to ionize the next neutral as well. In other words, the electrons re-supply themselves of energy in between collisions, courtesy of the electric field, so as to start the process again. This explains the 3GV per km: the energy necessary to ionize a loosely bound electron is roughly 3eV, and the path between collisions in the atmosphere is roughly 0.0001cm. This implies that a single electron will acquire 3GeV over a km (thanks to the electric field), which corresponds to a potential drop of 3GV over 1 km, exactly mins' figure.
The above also explains the sudden discharge: when then electric field exceeds the above threshold value, the number of electrons doubles every collision: the typical distance in air between collisions is 0.0001 cm, so that, over the course of 1km, a good value for the cloud thickness, one single electron would produce a cascade of 2^10^9 electrons. This number is unrealistically large (the total number of free electrons produced is limited the finite amount of energy available, roughly that of a capacitor of size 1km and electric field 3GV per km), but it gives a good idea of how a lightning is suddenly released. This is in fact a cascade, a sudden vacuum breakdown. For lower values of the elctric field, the newly formed electrons will not have sufficient energy to ionize the next neutral they hit; for larger values they will, thus causing a sudden increase in their numbers.

Airplane produce lightning ? YES. The thunderstorm electric field is multiplied by the airplane and may trigger lightning.
https://www.scientificamerican.com/article/what-happens-when-lightni/
Cloud formed over the wing of an airplane produce lightning activity just like some other kinds of "normal cloud"? NO. The charge it may hypotethically produce is order of magnitudine smaller if even created.


text:
Can I get an EASA ATPL online?
I have a PPL license in the US and I want to do a European ATPL license.
How does it work? Do I have to attend a school or can I do all online?
Do I have to physically take the tests somewhere in Europe or can this be done somewhere online as well? How did the COVID-19 change these things?

@StephenS What do you mean get there in the first place? I understand that the schools changed their policy and canceled all frontal instruction to presentations / zoom sessions / PPT. But regarding the theory tests- you say it still has to be on-premise of the school. Another question- what are the requirements regarding flight lessons and experience needed in order to get the ATPL? Please don't give me the "A lot!!!' Answer. If you have specific numbers- answer. if not- don't bother. You can also consider me having hundreds of hours logged already, aside from my ppl license.

Actually, it is very different. For example, 14 theory tests in EASA, while it's 1/ 2 exams if the USA. next- in order to actually get the license (meaning unfrozen ATPL)- you do need to take flight exams. Do you know the exact numbers for that? Because I knew that it was a lot by myself also.

@StephenS but what about air force veterans for example? Havr you thought about that possibility? I know these forums are a good ground for ego, but what i actually was here for- ie proper and accurate information. Yes, i have a PPL. And no, you did not give me one exact answer, just tried to satisfy your own craving for picking a weird argument online instead of being helpful. Which is a real pitty for you. I am sorry

This question might be relevant; EASA delegates licensing to member states and they can have different requirements. I'm not sure what your focus is here: how/if you can get an EASA ATPL in the US; how/if you can get an EASA ATPL online; how/if you can use an FAA private certificate as 'credit' towards an EASA ATPL; or something else? I think you're mostly asking about online but if my edit was wrong then of course please roll back or edit again.

@Stan are your comments referring Stephens answer? If so, you should place them under the answer. Your dismay at his anwer is somewhat unjustified, as your original question was not asking for very specific info. You may edit the question to make it more specific. Bottom line is, as Stephen wrote: it will not be easy, nor possible online, not by a long shot. To add insult to injury, there is no shortage of professional pilots now or in the near future.

@Jpe61 I made some snarky comments that I’be since deleted and turned into a more polite answer, but his replies are still here.

@Jpe61 Look, The fact is that instead of actually trying to answer and supply for information (and it's pretty obvious what information I need), we got to condescending and teaching morals. Of course, you can't get the whole license online, that is understood by everyone. Question is- Can you do the whole program online, except for the exams? or maybe- the exams must be taken on-prem? The flight experience is another question, to which Pondlife gave a good answer, and at least tried to supply some information.

No, you can’t get an ATPL online.
Your first step would be converting your FAA PPL to an EASA PPL. You will then need to add Instrument, Commercial Single-Engine, Commercial Multi-Engine, Multi-Crew Commercial and frozen ATP ratings. All of that will require ground instruction, flight instruction, written tests and checkrides. Then you will need to build time until 1500 hours to get your ATPL unfrozen. There are some differences in process and terminology between FAA and EASA, of course, but the end result will require roughly the same skills and experience because both systems have to meet the same ICAO standards.
COVID-19 has not changed the requirements to get a license, just the feasibility of actually meeting them. Many flight schools are closed, those that are open may not be accepting foreign students, and you may not be able to get there at all due to border restrictions.

S, I would argue that not everything you listed is a prerequisite for an ATP.  Unless you are sure that EASA is different than FAA...

@MichaelHall What do you think is unnecessary?

Well, I got an FAA ATP without ever having PPL, Commercial Single, or FAA Instrument Rating.  Yes, I was military, and the OP hints that he might be as well.  But, like you I am a bit put off by the way he asked the question, and his defensive response.

@MichaelHall He says “I have a PPL” in the question. Military pilots that start with a Multi CPL+IR can obviously skip the earlier steps.

Everything you mention is the “normal” progression of course, I am just pointing out that it doesn’t necessarily mean they are hard requirements.  If you amass 1500 hours as a Private pilot and can pass the ATP, why couldn’t you get it?

But if they are, add a reference to bolster your answer and I will upvote.

@MichaelHall That is my point- I do have a PPL which was acquired for recreational purposes. The flight hours are more than enough- I have more than 1500 hours logged. Now- for this situation- of course, the fact that I have an FAA PPl does not really help me a lot fo the European ATPL. Question is- with that experience, do I get any discounts regarding the flight experience? Will I have to do all the courses- IR, CPL, etc, or just the ATPL theories and exams? and Guys, don't get put off by my response. I am just trying to understand facts.

@Stan Those are critical details that should be included in your question. Yes, you get “credit” for the hours toward the time-building part. No, it doesn’t get you out of any other requirements.

Stephen, he did state in the question that he had a PPL.  And in his first comment he clarifies that he has hundreds of hours, so it is safe to presume that he understands that there is a minimum hour requirement.   And the question clearly is not asking what that flight hour minimum is.  I don’t know much about EASA, but surely there must be some document similar to our FAA CFRs that spell this out?

P.S.  I don’t even think that Stan’s background information matters.  If somebody asked what was required for an FAA ATP I could steer them to sub part G, or paraphrase an answer myself.  It would matter not if the asker was a commercial pilot with 2000 hours, or a school child writing a paper - the answer is the same.


text:
What is the origin of the "Pickle" switch for release of ordnance?
I am looking for proper proof of the theory that it is called so due to the Norden sight of the B17, which was said to assist the bomber in putting a bomb into a pickle jar, and hence it stuck.

Seems unlikely, as "Pickle" generally implies the emergency, unaimed, instantaneous release of all ordinance.

@quietflyer  No, I think the OP is right, although I don't have a source at hand. To "pickle" is simply to release; ideally with the precision that the bomb lands in the proverbial pickle barrel, but if necessary they land where-ever. (Hopefully, not armed, in the latter case.)

Pickle switch reference -- https://www.msn.com/en-us/news/us/boeing-inappropriately-coached-faa-test-pilots-during-review-of-737-max-after-deadly-crashes-senate-investigators-say/ar-BB1c3asu?li=BBnbcA1

The accuracy of the Norden bombsight was often exaggerated, but it was never claimed it could put a bomb into a pickle jar. The exaggerated claim from the Norden Company was that a bombardier using it under "ideal" conditions could put a bomb into a pickle barrel from 20,000 feet AGL. In reality it could barely get within 100 ft of the target from 10,000 feet AGL. (AGL = Above Ground Level) Some sources claim that it's called a pickle switch because a control handle with many switches almost feels like a pickle with all its bumps, but that would imply the name was given considerably later than WW2.

I would agree with the later because "pickle" is used in contexts other than releasing bombs, although who's to say it didn't evolve from that...

I also heard another theory, which says that the pickle switch naming was due to earlier submarines that launched Torpedos- which looked like pickles, and it then moves to the aviation world.

We made these in the 60s for USAF for release of PLADS AND LAPES SYSTEMS.  Comfortable grip and knobby for a good grip, hence pickle

Welcome to [Aviation.se]! Who is "we"? What are "PLADS AND LAPES SYSTEMS" and does it have to be ALL SHOUT CASE? Is this actually the origin of the term? Do you have any sort of reference that might support this claim?

LAPES


text:
Do FAA sectional charts show all power/transmission lines?
The FAA's sectional aeronautical charts include some power/transmission lines. How complete is this?
I am specifically interested in using something like ForeFlight for aeronautical charts while hot air ballooning. Is this a fool's errand?
If it is an incomplete reference for power/transmission lines, does anyone know what criteria the FAA uses for inclusion in the charts?

It is not complete by far. The FAA does maintain an obstacle database, but because it would clutter up the map they use some kind of criteria about when to show them or not. For example there are power transmission lines that run along the road by my house, neither the road nor the transmission lines are shown on the VFR map. I can't seem to find any information on how they decide to show an obstacle or not.

@RonBeyer Please don't add an answer as a comment

It isn't an answer though, I don't know the criteria they use to choose whether or not it's on the map.

In my experience the charts show many/most of the tall high tension power lines, but not the shorter lines. I don't know how complete the data is though.

Similarly, do not expect that all centenarys are charted.

From the FAA's Chart Users' Guide:

AeroNav Products’ charts are prepared in accordance with
  specifications of the Interagency Air Cartographic Committee (IACC)
  and are approved by representatives of the Federal Aviation
  Administration (FAA) and the Department of Defense  (DoD).

Book 2 of the IACC Specifications covers Sectionals and VFR Terminal Charts and provides the following guidance for transmission lines:

3.6.6.3 Telecommunication and Power Transmission Lines (T-Lines)
3.6.6.3.1 Landmark Value
T-Lines, if depicted on charts, are shown primarily for their landmark
  value. Determination of whether a T-line has landmark value or what
  constitutes chart congestion are matters of FAA Flight Edit judgment.
  Flight Edit shall either delete or add T-Lines on the Flight Edit
  Standard. T-lines with landmark value should be shown in open country
  and not in congested or built-up areas. Through open country, T-lines
  should be shown as continuous lines, interrupted only for reasons of
  cartographic practices. Location of the pylon symbol is dependent
  upon the length of the T-line; approximately at 1" intervals on a line
  3" or less in length, and approximately 2" apart on lines longer than
  3".

The transmission lines may also be charted under the rules of section 3.9.8.6 Obstructions.
So, no. T-Lines are not charted exhaustively. They are charted only when they have landmark value or are charted as an obstruction.


text:
What happens when a capacitor is supplied with a higher voltage than intended?
When a capacitor is supplied with a voltage of a higher frequency than intended, what will happen? Does the capacitor 'overheat' or 'resonate'?

I think you want Electronics SE.

Although a capacitor explodes with not insignificant force, the force is a brief impulse, and negligible in aerodynamic terms; the capacitor is consumed in the process, making it a very poor technique for sustained flight.

There is no effect of frequency (your question), as increasing frequency will change the current flowing in the component, but there is no power involved (current and voltage phases are at 90° phi). For overvoltage, it depends on the type of capacitor. Electrochemical capacitors are those prompt to "explode" due to the electrolyte solution converted into gas by heat. However this explosion is limited to paper fragments in a radius of one meter. Other capacitors will usually create a short circuit when the voltage is above the dielectric strength of the insulator layer.

A destruction of the electrolytic capacitor (caused by over voltage or reverse polarity) may lead to fire or explosion that are not a good thing to happen during the flight. Who wants to enjoy the video, here. This is not always, as electrolytic capacitors often contain safety vents to prevent explosions. Also capacitors should be rated to higher voltage than is normally applied to them.
Even if the capacitor just short-circuits, depending on how it is wired it may be a risk of fire. This is especially true for capacitors wired between the two power rails in order to suppress electric interferences between multiple power consumers and provider. When the failed capacitor short-circuits the rails, normally a circuit breaker disconnects the power. There are safety capacitors for use if this danger is a concern.
I was not able to find any accident reports related specifically to the failed capacitors.

I like how the video describes "lab experiment", however judging by the verbal comments "dude!", I find it highly suspect they are in a "lab".


text:
What is the difference between fail-safe and fail-soft?
I have heard the following terms related to safe system design but I cannot really see a difference between fail-safe and fail-soft (graceful degradation).
To get a common understanding I will just write out the terms that I've heard. Please feel free to correct me, if I don't explain something properly:

Safe life: A system does not show any fault during its lifecycle
Fail-Safe: A system goes into a safe operating mode with reduced functionality after a failure
Fail-Soft: A system goes into a degraded mode after a failure
Fail-Operative: A system still has the full functionality after a failure

From those explanations, it seems to me that Fail-Safe and Fail-Soft are actually the same concepts. I would be glad if someone could explain to me the difference between the concepts by using some examples from aviation.

Fail safe does not require system to operate at all.

Good example of fail-safe system outside aviation context are railway brakes. In passenger car force is applied to engage brakes, so when hydraulic system fails, you cannot use brakes to stop your car. In trains, however, brakes in neutral state are engaged and force is applied to hold them off. So any failure in power delivery engages them and halts the train pushing it into safe state - that's what makes them fail-safe, despite they are not "operable" nor have any functionality in failed state.

And safe-to-fail?

Fail-safe does not necessarily imply that the system will continue operating after a fail. If the system stops operating but does not create a dangerous situation, it is still fail-safe. A non-essential service on board an aircraft such as the entertainment system can be fail-safe if it just stops operating because a fuse blows. If upon a failure the fuse does not blow and as a result the system catches fire after a short-circuit, it is not fail-safe.
Fail-soft does indeed mean that after a failure, essential services are still functional, although in aviation context this is mostly referred to as graceful degradation. A fly-by-wire system such as on board the A320 is fail soft:

If all flight computers are functioning, the system flies with normal law active, providing protections against getting into unsafe regions of the flight envelope.
Upon certain detected failures, the system switches to alternate law, still with some protections in place.
Upon further failures, the system switches to direct law: no more flight envelope protections, just surface deflection proportional to stick deflection.

So this flight computer system is fail-soft and fail safe. The electronic flight control system as a whole is fail safe: if all flight computers are lost, the system has hydro-mechanical connections from pedals to the rudder and from the trim wheel to the stabiliser.
Hydraulic systems require special attention regarding fail-safety, since a stuck servo valve can command a constant velocity: the actuator runs into one of its stops and has a hard-over failure. An elevator that is stuck in full up deflection is not safe, so the pitch control system needs to make provisions for fail-safety if this fault occurs. For instance by allowing left and right elevators to normally work in unison, but uncoupling them after a detection of a hard-over failure. The working elevator can then be commanded to full opposite position, making the elevator system fail-safe but not fail-soft: pitch command must now be done with the stabiliser trim. One elevator stuck in the mid position would be fail-safe, and control with the other elevator provides graceful degradation.
The flight control system on board an F-16 is fail-operational: upon a system failure, full system function continues, no degradation. It is triple redundant, meaning there are four systems on board that carry out the same function, while only one is required. The four systems function independently, and a monitoring system determines if all four outputs are within a pre-determined range. If three are and one is not, this system is switched off and the other three continue. This can happen once more, but if there are only two systems operational the voting system would not know which of the two has failed.

Good description and examples. In my discussions with the FAA, they've very seldom used the term fail-soft. They typically refer to the key behavior of a fail-soft system which they term "graceful degradation" to the fail-safe state.

+1 Thank you for your clear and extensive answer. Finally, I can make sense out of these terminologies.

@Gerry indeed, fail-soft does not sound good in a military or aviation environment. Have included in the answer.

A loss of all hydraulics is not a common failure mode. It also is definitely not fail-safe. Because there is no cable connection on A320. The “mechanical” connection means a hydraulic one. If you lose all hydraulics, you are in serious trouble.

@JanHudec have amended.

I strongly suspect that the behavior of a F-16 after failure of one or more flight control system(s) depends very strongly on the cause of the failure. Some of those failure causes may not apply to typical airliner operation.

Slightly OT I find it odd that the F-16 has 4 independent systems. What if 2 are in agreement on one value and 2 are in agreement on another value? Granted, that's unlikely but not impossible - if weather is coming in from the right side, I could see the possibility of pitot tubes on that side freezing over while those on the left side remain clear. /OT thoughts

@FreeMan The system is likely a sophisticated hybrid running two overlapping TMRs or a single TMR with spare and or various split breaking systems either at the circuit elector level or within a controller.
I'm not familiar with the system but I do understand quad  N redundant systems, and they are usually anything as simple as an R(4,0),
Examples of deadlock breaking can be rejecting the longest service hour or elector rejection counts to remove a circuit, basically looking at its historical performance when no other measure is available. There are many options.

@Koyovis, is the F-16 really 4 similar systems with voting? That seems like a rather poor choice, because it does not guard against software bug (systems running the same code and seeing the same input would likely all make the same error). The Airbus system actually never votes on anything—it has dissimilar (both in hardware and software) primary and check board and if they disagree, they report fault and the next pair takes over.

@JanHudec The original analog FBW was.

@FreeMan: The F-16 has four so it can still hold a majority vote if one fails. This is actually triple-redundant (one system, three more for redundancy) but colloquially (and wrongly) called quadruple-redundant.

In my understanding, graceful degradation means that you are still able to limp home. No more capability to fulfil the mission, but enough to not crash immediately. For example, a single loss of a control surface would degrade handling from level A to level B (in the old MIL 8587 terminology) with more control forces and less authority. Or take the F8F, where the wingtips would snap off at 7.5 g instead of the full wing.

@JanHudec ('s first comment): A better example would be the 737, which does have manual reversion capability for the ailerons and elevators via ye olde mechanickale cables.

@Sean, I am not sure of what it is supposed to be a better example—the point was that backup for complete hydraulic failure is not required.